World Health Organization (WHO)
Thenalidine, a piperidine antihistamine, was introduced in 1953
for the management of dermatologic and allergic conditions. By 1958 its use had
been associated with cases of severe neutropenia, two of them fatal, which led to
its withdrawal in the United States of America and subsequently in the United
Kingdom. Over the next fifteen years, continued reports of its association with
cases of neutropenia resulted in further withdrawals in many countries. It is
apparently still available, however, in some combination products.
